如何将文本文件转换为字典？

Question

From a file, I am supposed to return a dictionary where each key is a person's name, and each value is a list with three elements in this order: the person's gender, the person's age and the person's height.

For example, if my file "file.txt" has two lines like this:

Peter, male, 18, 180
Andrew, male, 40, 175

Then the dictionary returned by this function would be:

{"Peter": ["male", 18, 180], "Andrew": ["male", 40, 175]}

I tried:

d={}
L=[]
f= open("items.txt","r")
for line in f:
    (key, val) = line.split(",",1)
    value= val.split(",")
    L.append(value)
    d[key] = L
return d
f.close()    

And it returns: {'Peter': [[' male', ' 18', ' 180 \\n'], [' male', ' 40', ' 175']], 'Andrew': [[' male', ' 18', ' 180 \\n'], [' male', ' 40', ' 175']]}

Answer 1

Your code is using the same L variable, resulting in an accumulation effect you don't want. Besides, it doesn't convert integers strings to integers, and doesn't remove end of line chars for the last item.

Other small mistake is returning the value and closing the file afterwards (this close statement isn't reached, so the file is closed whenever python decides. A with context manager is always better in those cases)

if f is your file handle (or a list of lines), this one-liner does the job:

f="""a,b,1,2
apple,banana,3,4""".splitlines()

d = {t[0]:[int(x) if x.isdigit() else x.rstrip() for x in t[1:]] for t in (l.split(",") for l in f)}

it splits according to comma, then builds a dict comprehension, using first item as key and other items as values, using rstrip to handle the newline of the last field.

The extra string to integer conversion uses isdigit so it's not perfect. (doesn't work for negative numbers). Can be replaced by an aux function.

result:

{'apple': ['banana', 3, 4], 'a': ['b', 1, 2]}